/*
 * $Id: TextElementCommon.java,v 1.1 2005/05/03 06:46:20 hamada Exp $
 ********************
 *
 * Copyright (c) 2001 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *       Sun Microsystems, Inc. for Project JXTA."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA" must
 *    not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact Project JXTA at http://www.jxta.org.
 *
 * 5. Products derived from this software may not be called "JXTA",
 *    nor may "JXTA" appear in their name, without prior written
 *    permission of Sun.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL SUN MICROSYSTEMS OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Project JXTA.  For more
 * information on Project JXTA, please see
 * <http://www.jxta.org/>.
 *
 * This license is based on the BSD license adopted by the Apache Foundation.
 ********************
 */

package net.jxta.impl.document;

import java.util.Enumeration;

import net.jxta.document.Element;
import net.jxta.document.TextElement;

/**
 * This class represent an element of a Text document. This class provides
 * some common things needed by TextElement instances.
 *
 */
public abstract class TextElementCommon implements TextElement {
    
    /**
     * Add a child element to this element
     *
     * @param element the element to be added as a child
     */
    public void appendChild(Element element) {
        if( element instanceof TextElement )
            ((TextElement) this).appendChild( (TextElement) element );
        else
            throw new ClassCastException( element.getClass().getName() + " not supported by appendChild." );
    }
    
   /**
     * Returns an enumeration of the immediate children of this element whose
     * name match the specified string.
     *
     * @param key The key which will be matched against.
     * @return enumeration containing all of the children of this element.
     */
    public Enumeration getChildren(Object key) {
        if( key instanceof String )
            return ((TextElement) this).getChildren ( (String) key );
        else
            throw new ClassCastException( key.getClass().getName() + " not supported by getChildren." );
    }
    
    /**
     * Get the name associated with an element.
     *
     * @return A string containing the key of this element.
     */
    public Object getKey() {
        return getName();
    }
    
    /**
     * Get the value (if any) associated with an element.
     *
     * @return A string containing the value of this element, if any, otherwise null.
     */
    public Object getValue() {
        return getTextValue();
    }
    
}
